Equalizing mechanism for four-wheel brakes



April 17, 1928. .1,666,881

c. LAMPRE EQUALIZING MECHANISM FOR FOUR-WHEEL BRAKES Filed Ausl. 26. 1925 2 Sheets-Shee 1 INVENTOR: QQS alam ze 5 BY j? C@ ci. @4* ATTORNEY# April17, 192s. 1,666,881 C. LAM PRE EQUALIZING MECHANISM FOR FOUR-WHEEL BRAKES Filed Aug. 25,. 1925 2 Sheets-Shee 2 l gfzlcm? fe) L., l' y ATTORNEY..

Patented Apr. 17, 1928.

o. UNIT-ED STATES onLEs'rIN mueran, or CLEVELAND, omo.

EQUALIZING MECHAMSMFOR- FOUR-WEEE# @ARES-1' 7 Application` inea riemergey1925.v serial Np. 52,672.

This invention relates to four-Wheel auto mobile brakes, and particularly to equalizing mechanism for brakes of this character.'

One object 'of the inventionv is to' provide brake jp'edal Alever commonly employed. I

an equalizing mechanisnr'which will l independently equalize thefront'yvheel brakes and the .rear vWheel brakes,an'd which will 'also' equalize bot-lisets of brakes.

A further object of the inventionistof W provide a self-contained eqnalizing mechanism which may be applied to any automo-` bile, and lwhich. is enclosed in a dust-prootl casing Whi h may v.form a reservoir for a suitable lubricantfin Which the parts may 1") Work, whereby the equalizing mechanismy Will -be protected against the ventrance of foreign substances and possible damage or injury, and kept lubricated and'atjalltimes for a Jree and easy Working action.

A still further Vobject ot the invention is to` provide an eqnalizing mechanism lwhich is simple oit construction,`

installed andai'iaintained vinr Working order at a comparatively lo7 cost. I

The invention consists ofthe tea-tures of construction, combination and arrangement ot parts, hereinafter fully described and claimed, reference being had to the accompanying drawings, in which :'-V

Figurel is a fragmentary top plan view in perspective `showing the applicaton of the invention-to an automobile chassis.

Figure ,2, is a top'plan viewl of the Inotion vtransmitting and eqnalizing mechanism'per se, with the cover of yits `casing removed. i

Figurev 3 is a vertical Vlongitudinal secs ing cover applied.

Figure 4 is a side elevation ofthe equalizingnieclianism shown in Figures. 2 and'3.

kFigure 5 isa sectional planview on line 'o 5 5 of Figure 3.

on line 6-1-6 of Figure 3.

Figure 7 is a vertical transversesection on f the shafts 12being Vpermanently'. mountedline 747 of Figure 3. Y

Referring I iolyvA .more iparticularly to the drawings, 1 designatestie chassis frame of an antornobile, 2 the automobile motor, 3 the 'propeller shaft driven vfrom the motor v 4 tl'noiigh the'usual'transmissionfmechanisrn,

reliable kand etiicent in operation, not liable to get out of' order, and capable of being manufactured,

tion on line 3-3 oft Figure 2, With'the cas-l 4 -the brake actuating rods leading to rthe front brakes, 5 the brake actuating rods yleadingto the'rear'vbrakes, and 6 a primary brake actuating (lever, which may be the have not deemed it necessary to show the brake devicesactuated by the rods 4 and 5,

, as lthose in common use or any others suited for .the purposemay be employed. l

` In carrying my invention into practice, I provide a brake actuating andV equalizing mechanism which is Voperatively coupled to thepedal or actuating device 6 for transmit- Yting brake applying motions to the rods 4,

and Thiswmotion .transmitting and f equalizing 'm`eclianism is enclosed Withiny a' suitable dust-proof casing 7, having a detachable top cover orclosure 8 and suitably i constructed for attachment to the chassis. Vframe 1, the'casing beingsh'own in the pres ent instance as vbolted' Vor riveted v to one of the side bars of thefchaslsisV frame. Journaled centrally in this casing 7 is a lhorizontal transverse rock shaft 9,4Which extends outwardly at' one side of the casing and has fixed thereto a crank arfm 10 coupled by aconnecting rod 11 tothe lever 6. vJournaled in the ends ofthe casingv 7 are pairs or sets of horizontal transverse rock shafts 12 to which arefixed motiontransmitting levers 13, arranged Within the casing. The shafts 12eXtend outwardly beyond opposite sides of the casing and are coupled toex'tension rock shafts 14 Provided with crank farms 15, the crank arms 15 of one pairor set ofr shafts 14 lbeing connected with the brake rods 4, While' the crank arms 15 of the other set of extension rock shafts are connected tothe brake rods 5, the forward set of levers `13 .thereforeoperatinglto transmit brake applying and releasingA motions to the front Wheel brakes, `and the rear setof levers 13 operating to transmitv brake applying and releasing motionsl to therear Wheel brakes.

o c In practice, fthe extension shafts 14, .wvhich' Figure 6 is a vertical transverse section Wit-hinl the casing 7, so that-all parts of the motion transmitting and Y equalizing mech7 VKanism .except `said extensionshafts will be self-'contained Within or by the casing, Vthe deemed-.its @erts .farming aait af wat" able type convenient of application to an automobile and of removal therefrom and of being shipped in a unitary or self-contained condition.

Pivotally coupled at one end by a clevis 1G to each lever 13 is a short chain section 17,`

preferably of sprocket chain type, andthe pair of levers 13 at cachend of the Vcasing are operatively connected bythe chains 17 attached thereto and to an equalizing lever 1,8, to the opposite arcuately shaped ends of which lever the chains 17 are pivotally coupled, as at 19. Each equalizing lever 18, is disposed transversely of the casing, at a point between its reacting motion transmit.- ting levers 13 and the center of the casing, andthe Vpivotal connections 19 are made between the inner ends Aof the chains 17 and the inne] or rcarrorners of said levers, between which pointsand their front corners such` arcuately shaped ends of the levers are formed with sprocket teeth 2O to engage the sprocket elementsof thev chains. By vthis construction each'r lever `18 israt all times positively coupled to the chain sections 17, butrmay` swing easily and freely laterally with respectV to either chain section for the purpose of permitting said chain sections and the levers' 13 to have differential motionsY for equalizing actions, as hereinafter described.l From the foregoing it will be seen that a. pair` of levers. 13 is arranged at each end ofthe casing 7, carried by independently movable rock shafts 14, which levers are coupled for conjoint motion vto equal degrees with an associated.equalizing lever 18, through the pivotal motions of which the levers 13 arepermitted to have variable or differential equalizing brake transn'iitting inQVementS, the equalizing lever mechanisms described being in duplicate at each end of the casing, one set being coupled to 4the front brake applying rods and the other set Ato the rear brake applying rods.

. The rock .shaft V9 carries within the casing 7 a secondary actuating lever 21, which is fixed centrally thereto, and which is adapted t-oreceive rocking'motions from the primary actuating lever l6 through the crank arm 10 and connecting rod 11'. This lever 21'is in the forni of a rocking` cross-head,compri-sing oppositely disposed and spaced disk portions or heads 21a united vat their front and rear sides by integral cross Vbars 21b and connected at top and bottoni by bolts 22 forining pivotal support-s for rollers or pulleys 231 disposed on opposite sides of or above and below the axis of thelevcri One disk or head'211 of this lever fornied Awitha socket 24'to receive the `shaft 9 which comparatively short and of a'length to fittherein, and' which is detachably secured in said socket by a pin orkey 25, and the other disk or head 21a of the lever is formed with a socket- 26 receiving a stub shaft' 2'? journaledin the opposite side of the casing and de-v tachably secured to said socket by a pin or key 28, a divided shaft construct-ion being thus produced so as to leave a clear guide space between the disks or heads of the lever and-between the inner peripheries of the allowing of the ready and convenient application and removal of the bearing elements and assemblage and disassemblage of the parts-of the secondary motion transmittingy lever, as will be readily understood. A inotion transmitting chain 33 passes through the center guidev space between the heads 21l of the lever 21 and between arms 21 and pulleys 23 and is thence'formedinto reversely projecting loops or bights passing around` the pulleys 23 in opposite directions, the` opposite'ends 34 and 35 of said chain being provided with clevises 36 which are coupled to and pivotally support the respective 'levers18 centrally of their ends, the said ends 34 and 35 of the chain 33 respectively forming draft connections between the lever 21 and the levers 18 coupled respectively to the front brake actuating rods 4 and the rear brake'actuating rods 5, whereby said brake actuating rods may be simultaneously operated. Coiled retracting springs 37 extend longitudinally of the casing 7 at each side thereof,`which springs 4are fastened at their outer ends to crank lugs 38 on the levers 13, the springs at each side being secured at their-inner ends by a screw 38" or the like to the adjacenty side of the casing.l The function of these springsv is by their contractile energy to returnthe elements of the brake mechanism tonormal position after each operative action thereof by the brakelever G and upon the release of pressure from the latter. If desired, the crank arm 10y may be provided with a stop lug` or extension 39 to abut against an adjustable stop member or screw 40 on the casing to limit the return movement of the lever 21 proper adju 1 ment being afforded for setting said lever at aproper starting positionv for an .accurate working action of the vparts.'opei'ated thereby.

InV the operation of the brake applyingV and equali'zing mechanism, assun'iing that both the front and rear brakes are in release posit-ion, it will be understood that when the lever is moved forwardly to transmit brakeA applyingaction tothe lever 21, thev latter-y will be rocked on its axis, through the intermediate connections lO'and 1l, to movcitt upper end forwardly and its lower end rearwardly, thereby drawing in opposite directions upon both chain ends 34 and 3,5 to

transmit brake applying motions to the rlevers 18, 'which will operate through the chains 17,. levers 13,'-rock shafts 12 and eX- tension rock shafts 14 to transmit brake applying motions to the brake Vactuating rods et and 5. If bothy sets of brake shoes or bandshave the same range of motion and apply with equal force within thesame operating period, the brake applying motion of the mechanism will Vbe uniformly transmitted thereto through/equal movements of all the working parts, as a result of which the end portions 3l and 35 of the cha-in v33, which are normally ofequal length, will remain so during the working movement of the lever 21, while the levers 18' will remain in a straight transverse position across` the casing and will'transmit equal brake applying motions through the chains 17 to the levers 13. If, however, one ofthe brakes of a pair, say'one of the front brakes yactu-ated by a rod 4, is applied with full force before its companion front brake, a brake apply motion of the lever 13 and chain 14 connected with the fully applied brake will cease, but the associated lever 18 mayqswing on its pivotal connection with thechain end 34 to allow the chain 17 and lever 13 coupled to the actuating rod 4 of the'un applied brake to continue their brake applying` motion until the latter-named brake is fully set, whereby an equalizing brake applying action of the front brakes will be established. The same action will occur with respect to the brake elements providedfor op-= erating the rear wheel brakes under the same conditions, so that an equalizing action of the rear wheel brake applying devices will be establishech The rollers 23 and the bight portions of the chainr 33 form members of a friction clutch connection between the ends of said chain and the lever 21, or between the levers 18 and the lever 21, whereby an equalizing connection of automatic character will lbe established between the front and rear sets of brake devices in the event that a compensating brake adjustment action between said Vsets of brake devices is necessary at any time in the actuation of theV brake mechanism in order to secure a proper regulated and positive braking action of the brakes on all four wheels. frictional engagement between the rollers 23 and chainY 33 is sutlicient to maintain a y lin any vrespect thereto, as equivalent devices and structural means for performing the functionsdescribed may be employed within iXed engagementbetween said parts for a brake applying action when the front and rear sets of brakes are fullyv set simultaneously upon a prescribed working movement of lever 21. If, however, one set of brakes is fully applied or set prematurely or before the other and before the lever 21 has made a full working movement, then and Normally the chain end connected with the fully set brakes causing a slippage of the chain about the rollers 23, the chain runningr over the rollers to the extent necessary to compensate for the relative variation in the motions required to apply both sets of brakes, whereby an equalizing action between the two sets of brakes is established. v When thebrakes are released and the parts returned by the springs 37 to normal position, the intermediate portion of the chain slips back over the rollers 23 to normal working position, thus re-establishing normal operating' conditions, yas willv .be readily understood. vIt will thus bek seen that my invention provides an equalizing mechanism by means ofV which an independent equalizing action will kbe established on either the front or rear wheel brakes, or'both, as conditions require, and also by means of which a relative equalizing action between both sets of brakes willsbe established when conditions require, and that the meclranism` providedv and not liable'to get out of order, and which f is entirely automatic in itscompensating and equalizing actions. Y y

An equalizing mechanism constructedfin accordance with my invention may be easily and conveniently applied to any type of auf. tomobile using four-wheel brakes without change in the construction of ythe brake mechanism of the Amachine and without change in operatingv connections except the simple changes required for coupling the brake lever to the equalizing mechanism and the latter to the bra-ke rods. The casing 7 may be of dust-proof character and designed to hold the lubricant in which the parts of' the equalizing mechanism may work, vby means of which' the equalizing mechanism will be protected from the entrance of dust, dirt and other yforeiffn particles and from injuryA by contact with extraneous objects,

ensuring easy'motion and long life to these the scope of the appended claims, without departing from the spirit or sacrificing any of the advantages of the invention.

kHaving thus fully described my invention, Y I claim: I f

1. In a four-wheel brake mechanism, front and rear pairs of separate and independent brake 'actuating levers, an equalizing lever for each pair of brake actuating levers, each equalizing lever having arcuately curved toothed end surfaces, sprocket chains connecting the ends of each eqnalizing lever with the coacting pair of brake actuating levers and engaging said toothed end surfaces of said equalizing lever, a primary opera-ting element, a rock shaft actuated thereby, a rocker lever actuated by said shaft and provided with arms on opposite sides of its axis, friction rollers carried by said arms, a chainpassing in opposite directions around said rollers and connected at its' ends with the respective operating levers, said chain being shiftablc on the rollers, and springs connected with the lrale actuating levers and rformally operative thereon to maintain the brakes in release position.

2. In a four-wheel brake niechanism, a casing, pairs of independent rock shafts at opposite ends of the casing, and journaled in the side walls thereof, a brake actuating lever carried by each rock shaft, a power applying rock shaft journaledin the casing between the brake actuating` rock shaft, a lever mounted in the casing and operated by aid power applying rock shaft, said'lever having arms on opposite sides of its axis, friction rollers carried by said arms, equalizing levers in the casing on opposite sides of said power applying lever and between the same and the pairs of brake actuating levers, flexible connections between each pair 1,eee,es1.

`of brake actuating levers vand the ends of the coacting equalizing lever, achain passingin opposite directions around thevrollers on the power applying lever and connected at its ends to the intermediate portions of the oppositely locatedequalizing levers, and

edges of' the equalizing lever and pern1aV nently connected therewith and with the respective motion transmitting levers, and mea-ns centrally connected with' the equalizing lever for transmitting brak-e 'applying motion thereto. l 1 f 4.' ln a four-wheel brake mechanism, front and rear brake actuating rods, an equalizing lever operatively coupled to each pair of rods, a primary actuating element,'a pair of spaced alined stub rock shafts, va pairv of spaced members carriedv by 4 said shafts, rollers carried by and between said members eccentric to the rock shafts, and a motion transmitting chain extending in opposite directions around saidrollers and coupled at its opposite ends to the respective' equalizing levers, said chain being adapted for running motion on the rollers for an equalizing action.

In testimony whereof I alliX my signature.

' CELESTIN LAMl)RE. 

